I am telling the scnario. I have page with all customer data as grid format. last column is "UPDATE". If I select 5th row and click update, next page open the details of 5th row customer data.My sql command:

$sql="select id,name,firstname,age from customer where id='$id'"

How can i pass the id for select customer to the next page to retrive data from mysql database and to update if any changes.